Foam reefer wall backing with spaced rows of loops for better adhesion

ABSTRACT

An improved reefer wall panel having better foam adhesion includes purposefully spaced gaps in the looped sections to be foamed. Such spaced gaps may extend horizontally, vertically, diagonally or in combinations of directions. These gaps (random or patterned) may be applied to the whole of a reefer panel or to just the more vulnerable lower sections where traffic impact during loading/unloading is more common and/or where delamination is known to occur more frequently. A method of reefer panel manufacture with such spaced gaps is also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a perfection of U.S. Provisional Application Ser. No.62/551,999, filed on Aug. 30, 2017, and a continuation-in-part of bothU.S. application Ser. No. 15/475,486, filed on Mar. 31, 2017 and U.S.application Ser. No. 16/017,955, filed on Jun. 25, 2018, all disclosuresof which are fully incorporated by reference herein.

BACKGROUND OF THE INVENTION

Applicant has used a polyester point bond fabric backing called “scrim”on his glass reinforced thermoplastic panels (GRTP) for interior wallsof refrigerated trailers, railcars, shipping containers, box trucks, andgeneral refrigeration (or “reefer”) storage units since 1998. The ideawas originally developed to get good bonding during manufacture of thereefer units. It was intended for the insulating foam poured between thecavity of the inner wall (GRTP) and outer wall (metal skin) to betteradhere to the latter. The foam soaks into and bonds to the polyesterpoint bond “scrim” backing. Applicant was granted a patent (U.S. Pat.No. 6,743,742) for his original system. Although the idea was novel andrelevant, it was later found to be too broad encompassing “any” panelrather than just panels used for the interiors of refrigerated trailers,truck bodies, container, and rail cars.

Since then, and consequently, the original “scrim” concept was adoptedas a standard practice and has been used by many competitors in thetruck trailer business that also supplies panels for refrigeratedapplications. Additionally, various methods to enhance this bond havebeen limited in their success. For example, lofting the scrim (creatinga brush to break surface fibers loose to create better bonding) or usingother materials/films to help chemically bond foam to panel do notinherently increase the bonding capability of the scrim surface.Applicant now believes he has a significant improvement to that earlierdesign.

The goal is to produce a panel with a unique and varied method ofbonding to the foam for the reasons set forth herein. Fork trucks andother freight loading mechanisms create tremendous pressure and damageto the inside of a refrigerated unit resulting pressure against the wallas cargo gets stacked in such units. In these cases, the pressure causesbond of “scrim” to foam to separate because the wall's inability to holdonto the foam (grab factor) is less than the pressure exerted. Theresult is wall delamination from the foam structure and a wall that nowis compromised. Since units useful life is up to fifteen years, theseparation of the foam to the wall is critical in the longevity of theunit. The scrim helps to grab the foam but methods to scrape or loftscrim, use of films, and other methods of bonding foam have noteliminated the problem. When the wall delaminates from the foam, itallows moisture to infiltrate, resulting in potential damage andultimate costly repair or replacement of the interior wall.

One known process gets scrim to stick to the back of material comprisedof a glass-reinforced polypropylene tape that is layered and thenlaminated into each panel. That lamination process melts, compresses,and then cools product in a continuous process. The scrim is a“fiberized PET point bond” fabric with a higher melting point than thepolypropylene so when it is laid atop of applicant's product and runthrough the lamination process, it does not melt along with the wholestructure. Rather, it absorbs the polypropylene during the meltingprocess. Applicant has now developed a way for his applied polypropyleneto NOT absorb all the way through. As such, when his product getsfoamed, the backside will allow the “foam soak bond”.

Other Relevant Art

In chronological order, they include:

Lowthian U.S. Pat. No. 3,934,064 disclosed a composite structure ofknitted glass fabric and thermoplastic polyfluoroethylene resin sheet.FIG. 4 therein showed, in an enlargement, a single loop of yarn (fromknitted glass fabric) containing a monofilament of a “melt-fabricableperhalopolyfluoroethylene” polymer resin. The composite structureincorporating that fabric was claimed to have correspondingextensibility.

Adams U.S. Pat. No. 4,474,635 disclosed a cushioned panel and a relatedmethod of molding it. For the panel, a non-woven fabric with an outerlayer of polypropylene or other thermoplastic was heated to the meltingpoint of the fibers before being inserted into a mold with a decorativesurface fabric and piece of foam cushioning. The mold was designed sothat edges of the male and female mold halves compress for forcing themolten surface of that substrate into interstices of the surface fabric.

Ott et al. U.S. Pat. No. 4,761,318 disclosed a disposable diaper thatemployed a soft flexible sheet-like fibrous structure with amultiplicity of loops along a first surface, and a layer ofthermoplastic resin adhered to a second major surface for anchoringthose loops in the fibrous structure. It has no equivalence whatsoeverto trailer/container walls.

Novak U.S. Pat. No. 6,863,970 disclosed a product consisting ofpolyethylene and polypropylene with at least one sheet of fibrousmaterial that enabled bonding of the polyolefin to a non-polyolefinfoam. The combination also preferably included a fastener havingthreaded portions positioned within the foam which threaded portions arenot easily removed when an outward force is applied.

Hedley et al Published U.S. Application No. 20100040839 disclosed amethod and apparatus for making an embossed thermoplastic liner panelfor the interior of a cargo transporter/trailer. The invention inserteda release film between its reinforced polymer feedstock and animpression mat.

Erickson et al. Published U.S. Application No. 20130025766 disclosed aloop fastener material finished by applying foam to a surface of thefabric, that foam containing both a liquid binder and a powder. Thatbinder was allowed to flow into pores of the fabric and coat fiberinterstices as the foam collapses. Then, it was dried to stabilize thefabric. The particle size of that powder was selected to cause most ofit to remain on the fabric surface while the binder is dried. Thatfabric surface, with powder bonded thereto, was then activated by heat,RF or UV energy for adhering to yet another surface.

Finally, Lookebill et al. Published U.S. Application No. 20150246511disclosed a thermal insulated composite wall panel for insulatedtrailers. The panel included a first liner panel, second liner panelwith a layer of fibers and at least one structural polymer resin layerdisposed coplanar to and bonded with the fibers layer.

SUMMARY OF THE INVENTION

The products of the parent application employ an improved “looped”fabric backing for the manufacture of glass-reinforced thermoplasticpanels, said loop fabric backing exhibiting a several fold increase (ora 100%, 150% or as much as a 200% greater foam adhesion) than its pointbond scrim counterpart. Another product in the parent filing is theimproved glass-reinforced thermoplastic interior wall panel that is madeusing the aforementioned loop fabric backing. Yet a third improvedproduct therein is a storage unit, such as a refrigerated trailer,railcar, shipping container and/or box truck having interior wall panelsfoam adhered to this new and improved loop fabric backing. The latterproduct would be more damage resistant than its earlier scrimcounterparts.

A method for making such improved products starts with (a) providing animproved “loop” fabric backing substrate; (b) providing a single ormultiple 0/90, 0/45 tape, or a woven glass reinforced polymer layer(preferably, polypropylene); (c) providing a surface film made oflightweight scrim coated with polypropylene and having a PET-integratedrelease liner; (d) combining elements (a) through (c) and feeding theminto a continuous flatbed laminator or similar lamination line forheating and pressing; then (e) cooling the product exiting the laminatorto make a glass-reinforced thermoplastic interior wall panel therefrom.

A further novel method of the parent invention entails making animproved storage unit, such as a refrigerated trailer, railcar, shippingcontainer and/or box truck with a plurality of the aforementionedglass-reinforced thermoplastic interior wall panels. That unit willexhibit greater adhesion inside of its interior wall panels, resultingin less potential downtime and loss of thermal efficiency from damagefrom container packers and/or during packaging transport. Due toincreased foam adhesion, such units will have reduced repair/replacementcosts and a prolonged useful life.

For the present invention, i.e., the subject of this case, there isdisclosed an improved reefer wall panel having better foam adhesion byincluding purposeful spaced gaps in the looped sections to be foamed formaking the reefer wall panel. Such spaced gaps can extend horizontally,vertically, diagonally or in combinations of directions. These gaps(random or patterned) may be applied to the whole of a reefer panel orto just the more vulnerable lower sections where traffic impact duringloading/unloading is more common and/or where delamination is known tooccur more frequently.

BRIEF SUMMARY OF THE DRAWINGS

Further features, objectives and advantages of this invention willbecome clearer with the following Detailed Description made withreference to the accompanying drawings in which:

FIG. 1 is a photograph showing currently known scrim with its very smallfibers in just the x and y-axes;

FIG. 1A is a photograph showing the standard scrim bond of FIG. 1 withits attached foam partially peeled away;

FIG. 2A is a cross sectional view of a lower half hook and loop tape asused with the present invention;

FIG. 2B is a front plan view of a first embodiment of improved reeferwall having a plurality of hook tape sections applied in a spaced,horizontal arrangement from near the top to near the bottom of the wallprior to foaming;

FIG. 2C is a front plan view of a second embodiment of improved reeferwall having a plurality of hook tape sections applied in a spaced,diagonal arrangement from near the top to near the bottom of the wallprior to foaming;

FIG. 2D is a front plan view of a third, representative embodiment ofimproved reefer wall with a plurality of circular-shaped hook tapesections applied randomly to just a lower section of the wall (in morevulnerable regions for delaminating) prior to foaming;

FIG. 3 is a diagrammatic representation of one prior art variety ofmultiple thread/strand fabric inter-looped to one another but with nobase connection, per FIG. 3a of U.S. Pat. No. 3,934,064;

FIG. 4 is a diagrammatic representation of a second prior art foambacking system, this time with a single thread/strand having one endinto a polymer base but no interweaving therethrough, per FIG. 7 of U.S.Pat. No. 3,934,064;

FIG. 5 is a cross-sectional diagram of a third prior art variety ofmaterial showing means for randomly embedding continuous strands offabric into and at least partially below an innermost layer; but itexhibits no connection on randomness, per FIG. 8A of U.S. PublishedApplication No. 20150246511;

FIG. 6 is a cross-sectional diagram of a fourth prior art variety ofmaterial showing embedding strands of fabric with multiple downwardextensions (in one common direction) from its innermost layer, per FIG.8B of U.S. Published Application No. 20150246511;

FIG. 7 is a front perspective view showing one system of foam reeferwall according to this invention, said foam reefer wall employing oneembodiment of loop scrim fabric backing for improved foam adhesionthereto, all interconnected using one continuous fiber creating base andloop together;

FIG. 7A is a close-up sectional view of the circled area 7A from FIG. 7,showing loops of a substantially uniform or constant height;

FIG. 7B is a cross-sectional view of a first alternative embodimentshowing loops with purposefully variable heights, 118 a, 118 b and 118c;

FIG. 7C is a top perspective view of a second alternative embodimentshowing intentional loop gaps in both the horizontal GH and vertical GVdirections;

FIG. 7D is a close-up sectional view of the circled area 7D from FIG.7C;

FIG. 8 is a top perspective photograph showing, from one edge, anembodiment of loop scrim fabric backing per this invention;

FIG. 9 is a close-up diagram showing or how the loops are interwoveninto the base per one embodiment of this invention;

FIG. 10 is a close-up diagram focusing on one row of preferred loopswith base material per this invention; and

FIG. 11 is a perspective, sectional view of a refrigerated vehicletrailer showing the improved loop scrim fabric backing of this inventioninstalled on the interior of the same.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

When referring to alternate embodiments, like that shown in FIG. 7B,common elements are commonly numbered though in the next hundred series.

When referring to any numerical length, width, percent improvement orother quantitative comparison number (or number range) herein, it shouldbe noted that all such numbers are representative of embodiments of theinvention as shown. Furthermore, any such range of numbers shouldexpressly include each and every fraction or decimal between its statedminimum and maximum. For instance, any one component (of loop material)having from about 40 to 70 loops per square inch, should alsospecifically cover fabric backing substrates having about 41, 42 and 45loops/in² . . . and so on, up to about 65, 67 and 69.6 loops/in². Andfor loop heights between abut 0.5 to 6 mm or more, preferably about 3 to5 mm each, those loops would include all values between theaforementioned minimum and maximum loop heights. It is to be understood,however, that Applicant considers the mere aspect of creating suchlooped scrim fabric backing, regardless of loop size/consistency and/orrelative loop density to be a truly novel, game-changer aspect of thepresent invention.

A fabric backing with at least about 30% greater foam adhesion ascompared to its scrim counterpart, would also exhibit about 35, 40 and50%+ improvement. The same applies for every other quantitative rangeherein.

FIG. 1 shows a 37× magnification of current “known” standard scrim panelas might be made and sold by Xamax Industries, Matterworks and/or OXCOIndustries to name a few. Unfortunately, therein, the underlying panel Phad its foam F separated therefrom with the application of nominal pullpressure due to a weakness of adhesion at the interface between asbetter seen in accompanying FIG. 1A.

Note the following difficulties/disadvantages with that product:

1) fibers are very small—in only the x- and y-Axes (marked therein);

2) there are indentations where the fibers have been connected via aheated “point bond” roller;

3) it is a much denser product—harder to soak into during foamingtherefore resulting in worse bonding; and

4) this point bond product is made of two layers bonded together, whichcould allow separation. It is especially vulnerable to separationespecially when moisture is introduced.

FIG. 1A is a photograph showing a prior art panel P with its standardscrim bond B, like that shown in FIG. 1, when attached to foam F butthen that latter foam F is partially peeled away.

Accompanying FIGS. 2A through D shows Applicant's newest development. Itexhibits much advancement and improvement over the current scrim ofFIG. 1. The underlying material has a plurality of loops extendingupwardly therefrom before being combined with foam by injection duringthe manufacture of trailer and other GRTP materials/component parts. Theresulting product exhibits much greater adhesion at its interface.

More particularly, FIG. 2A is a drawing showing a cross section of the‘lower half” of a hook and loop tape T, more often referred to by thename Velcro®, with its barbs or hooks H diagrammatically depicted asextending upwardly and along a section of adhesive tape backing. Asecond section of looped fabric, not shown in this view, would belayered onto the aforementioned hook components and with nominal appliedpressure forced into the hooks for readily interlocking therewith. Suchconnections are reusable, however, as the upper loops can be pulled awayfrom the hooks and then repeatedly rejoined thereto;

FIG. 2B is a drawing showing a first embodiment of improved reefer wallW with a plurality of lateral hook tape sections (l₁ through l₆) appliedin a spaced, horizontal arrangement from near the top 10 to near thebottom 20 of wall W prior to the application of foam thereto;

FIG. 2C is a drawing showing a second embodiment of improved reefer wallW with a plurality of hook tape sections (d₁ through d₇) applied in aspaced, diagonal arrangement from left to right, from near the top 10 tonear the bottom 20 of wall W prior to the application of foam thereto;and

FIG. 2D is a drawing showing a third, representative embodiment ofimproved reefer wall W with a plurality of circular-shaped hook tapesections c applied randomly to just a lower section 20 of wall W (in atypically more vulnerable region for delamination or loading damage)prior to the application of foam thereto. These are but three sucharrangements, it being understood that still other arrangements of fullhook tape, various subsections of hook material (in rectangles, squares,triangles, etc.) may be randomly or purposefully placed about in anorderly pattern prior to “foaming”. To a lesser degree, the looped“partner” to such hook sections may be situated about, in place of(i.e., in the alternative) OR in addition to the placement of the hooksection tapes there along . . . prior to the addition of foam to thesereefer wall units.

Main steps to this invention include:

-   -   1) Replacing standard scrim by laminating a PET backing that has        a polypropylene film layer on one side and urethane surface on        the other side.    -   2) The urethane surface would face the foam and provide a        chemical bond to the urethane foam.    -   3) Then we would place strategically half of an adhesive backed        Velcro® or the “Vel” if you will (i.e., just the male or hook        portions of such material) along various points of the wall for        better adhesion of foam to these sections of strategically        placed Velcro tape halves.

Advantages are that this alternative to the use of full loop sheetmaterial (the subject of its own pending U.S. application, also filed inthe name of Applicant) is much cheaper than the aforementioned. Thesesubsections of hook-only strips (or shaped sections) can also be placedon any time after the panel has been laminated thus allowing for astrategic yet inexpensive way to get the foam bond without laminating.

The use of hook tape and/or shaped sections per this invention alsoavoids the potential for “looped only” material assists getting buriedinto the surface like the loop fabric might during lamination. Thematerials being used hereby only use adhesives per se and do not HAVE TOBE laminated into the surface of the panel in order to bond to it.

Configurations, shapes and angles of VEL are only limited by therequirement of the application. Furthermore, it should be understoodthat this invention can be practiced on whole wall or just on the bottomsections thereof. There should be no distinction other than the conceptof why we are doing this. It should be cheaper than but still just aseffective as loop.

Still other advantages of this improved product include:

1) a fiber loop design that has been woven into a pattern extending farbeyond the surface of the panel. That allows for the foam to cure aroundthe loops to the bottom connection point and create a much deeper “grabfactor”. That, in turn, allows for the wall to exceed the surface bondobtained by the current methods of scrim and create a more permanentbond, deep into the cured foam, for solving the delamination issue ofprior products.

This is truly a game-changing, MAJOR improvement! When the foam attachesto the wall, the raised “loop” fibers of this invention will grab andhold much better than just an X and Y axis product. The presentinvention adds a looped dimension to the equation thus making for anoverall stronger interior panel. Even if the standard scrim was loftedor roughed up to provide an exposed Z-fiber, as per accompanying FIG. 6,there is still no loop mechanism equivalent that can provide themechanical grab and reconnection to an interwoven base/bottom that thisconcept does.

2) The design of the new “loop” has a uniform grid base (loop densitycan be varied to accommodate different foam compositions and densities)that allows for excellent attachment to applicant's base polypropylenewall and glass mat products so that it holds better.

3) The “loop” design is impervious to moisture unlike old scrim materialthat can separate when wet into two point bond layers from its pointbond.

4) Applicant's polypropylene can soak through this product during thelamination process thereby allowing for a better grab to the trailerinterior GRTP wall than the traditional scrim product, a potentially50%, 75%, even 100% or more adhesion than standard scrim, in fact.

5) Loop fabric can be applied by either laminating on OR gluing to thebackside surface of the wall allowing for maximum optional usages in thefield.

6) Loop fabric can be of any material such as a polyester, nylon,polypropylene, polyethylene, etc., but should be stiff enough to holdits shape without flattening out as the trailer wall is rolled forshipping or placed into a foaming chamber.

One set of preferred method steps for making this improved materialproduct commences with: (a) providing an improved fabric backingsubstrate having a plurality of loops interwoven therewith; (b)orienting the plurality of loops in the backing substrate to “stand” ina raised (rather than flattened) condition; and (c) injecting a polymer(preferably, polypropylene) foam about the raised loops for greaterimpregnation of the polymer into the backing substrate for themanufacture of a trailer scrim/glass-reinforced thermoplastic interiorwall panel.

A further novel method entails making an improved storage unit, such asa refrigerated trailer, railcar, shipping container and/or box truckusing a plurality of such glass-reinforced thermoplastic interior wallpanels. That unit will exhibit greater foam adhesion within saidinterior wall panels, resulting in less potential damage from containerpackers and/or during packaging transport. And, due to this increasedfoam adhesion, such units will have reduced repair/replacement costs anda prolonged useful life.

Applicant believes his improvement fully exploits the revolutionary“loop” fabric that his method employs. That looped design is not thesame typical Velcro® underlayment nor even one half of what makes upstandard Velcro tape, i.e. the hook OR the partnering loop side. Thelatter's loops are much smaller and merely intended to coordinate (i.e.mesh) with the hooks of the other material half. It would not bepossible, nor practical, to incorporate a full or half portion oftypical Velcro® tape for achieving the desired adhesion levels observedwith the present invention.

The aforementioned loops may be standard/uniform or continuous inrelative height to the interwoven base as per FIG. 7A. Alternately,another embodiment would address improvements using loops of variableheights, such as the short, medium and tall loop heights 118 a, 118 band 118 c for product 110 in accompanying FIG. 7B.

This invention improves the performance of reinforced and non-reinforcedpanels used for interiors of refrigerated transportation equipment.Admittedly, surface treatments are used all the time for improvingadhesion with glues, etc., but this new dimensional “loop” is trulynovel in its unique improvements in this field of use.

Two representative sizes of fully looped materials, made for Applicantby Apex Mills, were manufactured for size comparison purposes. The firstwas designated RH87 loop material (as seen below):

STYLE CONTENT: RH87 TEST METHOD 100% POLYESTER ASTM D629 WEIGHT (oz/sqyd):   5.3 +/− 10% ASTM D3776 WALES (width)/inch: 9 +/− 1 ASTM D3887COURSES (length)/inch: 27 +/− 3  ASTM D3887 INSTRON BALL BURST MIN 75ASTM D3787 (lbf): MULLEN BURST: N/A ASTM D3786 THICKNESS (inch): 0.18+/− 0.02 ASTM D1777 TENSILE (LENGTH) N/A ASTM D5034 (WIDTH) N/A ASTMD5034 AT BASE 117 Loops/sq inch +/− 12 Loops Loop height:  6 mm +/− 0.6mm Loop height:  4 mm +/− 0.4 mm

For a smaller, more compact style of fabric backing, a second scale ofsubstrate was made and tested. Called RJ30, its particulars are asfollows:

STYLE CONTENT: RJ30 TEST METHOD 100% POLYESTER ASTM D629 WEIGHT (oz/sqyd):   4.3 +/− 10% ASTM D3776 WALES (width)/inch: 9 +/− 1 ASTM D3887COURSES (length)/inch: 27 +/− 3  ASTM D3887 INSTRON BALL BURST MIN 75ASTM D3787 (lbf): MULLEN BURST: N/A ASTM D3786 THICKNESS (inch):  0.11+/− 0.011 ASTM D1777 TENSILE (LENGTH) N/A ASTM D5034 (WIDTH) N/A ASTMD5034 AT BASE 63 Loops/sq inch +/− 6.5 Loops Loop height:  5 mm +/− 0.5mm Loop height:  3 mm +/− 0.3 mm

RH87 and RJ30 are both warp knitted fabrics utilizing a uniqueconstruction where 2 multifilament yarn systems form the substrate and a3^(rd) heavy gauge monofilament yarn system is anchored on 1 needle andcast off on the alternate needle to form a loop on one side of thefabric while leaving the alternate side of the fabric smooth. Both RJ30and RH87 are made with 100% Polyester but other yarn types can besubstituted therefor.

FIGS. 3 through 6 show other relevant material modifications prior tothe parent application AND the present invention. FIG. 3 shows loopedlayers L onto one another in a typical fabric material. FIG. 4 shows aprior art substrate S from which a single strand of line is embeddedfrom only the adjoining base elements B. FIG. 5 shows a prior art scrimsection with its non-woven mat M beneath composite sheet C, similar tothe main disclosure of Applicant's U.S. Pat. No. 6,743,742. And FIG. 6is a modified variation of FIG. 5 with an intentionally roughed up outerfibrous layer O which still does not achieve the bond adhesion levelsobserved with the present invention.

FIGS. 7 and 7A show one preferred embodiment of interior wall panel 10made according to the parent invention. The exterior, metal wall to thatpanel is indicated with a TM designation and its innermost wall panelinterior with a TI designation.

Said wall panel 10 has a base material 12, into which is sewn a speciallooped fabric backing, generally 14, consisting of an underlyingsubstrate layer 16 from which a plurality of polymer loops 18 areinterwoven and outwardly extend. The latter loops are encased in anouter foam layer 20 for subsequent lamination to form the wall panelproper. Such loops are necessary and critical for integration into thebase for making an improved GRTP product hereby.

FIG. 7B shows an alternate embodiment of wall panel 110, with its ownfabric backing 114, and corresponding substrate layer 116 from whichthree representative heights of variably sized loops, 118 a, 118 b and118 c are interwoven, and then combed or brushed upward to “stand atattention” prior to being foamed about.

FIGS. 7C and D show a second alternate embodiment of wall panel 210,with its own fabric backing 214, and corresponding substrate layer 216from which one representative height of loop 218 is interwoven but withpurposeful loop gaps added (either randomly as shown, or in a presetpattern) in the horizontal direction GH, vertical direction GV or both.Though shown much smaller for ease of illustration purposes, a typicalloop gap, either horizontal or vertical, may be as much as 12 inchesthick, or range from about 1 to 10 inches, more preferably about 3 to 5inches high (for horizontally extending spaces), or wide (for verticalspaces).

FIG. 8 is a photograph depicting a forward edge to a representativesection of the base material from FIGS. 7 and 7A with its rows ofinterwoven fabric backing attached thereto and its plurality ofconsistently-sized loops 18 extending upwardly therefrom . . . allbefore encasement in the foam to make the improved interior wall panelof the parent invention.

FIG. 9 shows an underside of substrate layer 16 (lined) from which therespective rows of loops 18 (unlined, for better illustration) areinterwoven. Note how all of the loops tie into the base or weave ofsubstrate layer 16. That base is necessary for embedding into thelaminate product: the base sticks to the trailer backing interior TIwhile the loops of that product “stick” firmly into the foam injectedbetween the interior TI and metal exterior TM.

FIG. 10 shows a close up view of one representative row of loops 18 witha single braid of the substrate layer 16 wrapped thereabout consistentlylined like the two components in preceding FIG. 9.

Finally, FIG. 11 is a representative trailer product with an exteriormetal TM surface, showing in cutaway to expose one of its interior wallsTI made using the panel improvements 10 of this AND the parentinvention.

The primary focus of this invention is to replace full sheets of loopmaterial with sheets having intentionally spaced, or gapped, sections.In other words, this invention uses sheets with either much smaller (orshorter) loops or no loops whatsoever . . . in certain rows (horizontal,vertical, diagonal, or even more random) for improving the adhesion offoam to these spaced/gap sections of loop sheets.

Further advantages of this alternative to sheets that are fully looped,i.e., having repeated rows of loops {in either the same height or invarying heights) across the whole face (i.e., surface area) of saidsheets prior to foaming, are both cost and ease of manufacture. In otherwords, a purposefully gapped section of loop material would be more“forgiving” and lead to fewer rejections in manufacture/assembly ofpanels therewith.

Having described the presently preferred embodiments, it is to beunderstood that this invention may otherwise be covered by the scope ofthe provisionally filed claims that follow.

What is claimed is:
 1. An improved reefer wall panel having better foamadhesion thereto by including one or more rows of spaced gaps in loopedsheets to be foamed for making the reefer wall panel.
 2. The reefer wallpanel of claim 1 wherein the rows of spaced gaps extend substantiallyhorizontal in the looped sheets.
 3. The reefer wall panel of claim 1wherein the rows of spaced gaps extend substantially vertical in thelooped sheets.
 4. The reefer wall panel of claim 1 wherein the rows ofspaced gaps extend diagonally in the looped sheets.
 5. The reefer wallpanel of claim 1 wherein the rows of spaced gaps extend randomly acrossthe looped sheets.
 6. The reefer wall panel of claim 1 wherein the rowsof spaced gaps extend in a preset pattern across the looped sheets. 7.The reefer wall panel of claim 1 wherein the rows of spaced gaps have noloops extending upwardly from a base substrate.
 8. The reefer wall panelof claim 1 wherein the rows of spaced gaps have one or more short loopsextending upwardly from a base substrate.
 9. The reefer wall panel ofclaim 1 wherein the rows of spaced gaps extend in at least one of: highimpact areas and high delamination areas of the reefer wall panel. 10.The reefer wall panel of claim 1 wherein the rows of spaced gaps extendin other than a high impact area or a high delamination area of thereefer wall panel.
 11. The reefer wall panel of claim 1 wherein the rowsof spaced gaps range in size from about 1 to 10 inches high or wide. 12.The reefer wall panel of claim 11 wherein the rows of spaced gaps rangein size from about 3 to 5 inches high or wide.
 13. A method for makingan improved reefer wall panel having better foam adhesion, said methodincluding: providing at least some of looped sheets to be foamed formaking the reefer wall panel with a plurality of spaced gap rows priorto foaming.
 14. The method of claim 13 wherein the spaced gap rows inthe looped sheets extend substantially horizontal.
 15. The method ofclaim 13 wherein the spaced gap rows in the looped sheets extendsubstantially vertical.
 16. The method of claim 13 wherein the spacedgap rows in the looped sheets extend diagonally.
 17. The method of claim13 wherein the spaced gap rows in the looped sheets extend randomly. 18.The method of claim 13 wherein the spaced gap rows have no loopsextending upwardly from a base substrate.
 19. The method of claim 13wherein the spaced gap rows range in size from about 1 to 10 inches highor wide.
 20. The method of claim 19 wherein the spaced gap rows range insize from about 3 to 5 inches high or wide.